<!-- 翻转数组 [1,2,3,4,5] => [5,4,3,2,1] -->

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<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
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<body>
    <script>
        var arr = [1, 2, 3, 4, 5];
        for (var i = 0; i < (arr.length / 2); i++) {
            var temp = 0;
            temp = arr[i];
            arr[i] = arr[arr.length - 1 - i];
            arr[arr.length - 1 - i] = temp;
        }

        console.log(arr);

    </script>
</body>

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